This is great, because it means you can track the activity of transcription factors and see what parts of the network are active when...and then use that information to try to figure out the role that networks of transcription factors play in important cellular tasks like "changing gears"...switching from proliferation mode to specialization/maturation mode. Figure this out, and you might get your head around a lot of interesting questions...including how some cancers arise, and how tissues and organs form.